Variable condenser



sept. 1s, 192s.

J. LYONS JR VARIABLE coNDENsER Filed May 18, 1925 3 Sheets-Sheet 2IM/manioc:

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JW M0 Mw Patented sept. i1a, 192s.

UNITED STATES 1,684,964 PATENT' OFFICE.

JAMES LYONS, JR., 0F NEW YORK, N. Y., ASSIGNOR '.lOl SELF AND LEO H.SCHWAB- .ACHER, TRUSTEES, 0F NEW YORK, N. Y.

VARIABLE CONDENSER.

Application led Hay 18, 1925. Serial No. 81,056.

This invention relates to improvements in radio apparatus, and moreparticularly to condensers therefor of the variable type.

The primary object in view is the obtaining of extreme nicety andprecision of adjustment. A further object in view is the compoundingl ofthe actuating means for enabling an initial, approximate adjustment anda subsequent refined adjustment. 4

A still further object is the actuation of the movable element of avariable'condenser by control located at any convenient point on a panelregardless of the location of the contained condenser.

1With these and further objects in view as will in part hereinafterbecome apparent and in 'part be stated, the invention comprises certainvnovel constructions, combinations and arrangements of arts assubsequently specified and claimed? In the accompanying drawings,

Figure 1 is a plan view of a condenser embodying the features of theresent invention illustrated in a housing shown broken away with a panelseen in horizontal section.

Figure 2 is a view in Side elevation thereof, the housing and panelbeing seen in vertical section and the panel control being seen in edgeview. i

l Figure 3 is a transverse, vertical section taken on the planeindicatedby line 33 of Figure 2.

Figure 4 is an enlarged, detail, fragmentary, sectional elevation, thesection being taken on, the plane indicated by line 4-4 of Figure 3, andlooking downward.

Figure 5 is a front elevation` of one of the panel controls detached.

Figure 6 is a vertical, central section therethrough, parts being seenin elevation.

Figure 7 is a transverse section taken approximately on the planeindicated by line 7-7 of Figure 6, looking downward.

Figure 8 is a similar section taken on the plane indicated by line 8 8of Figure 6, looking upward.

Figure 9 is a view similar to Figure 3 of a slightly modifiedembodiment.

In radio receiving apparatus, as iswell known, it is important forclarity of reception that as nearly as possible the exact v condenserefect be obtained. The importance of the relative shifting of the platesof a variable condenser cannot be exaggerated, and it frequentl happensthat the wave lengths of sendmg stations are so nearly alike that adifference of considerably` less than one point on the condenser vernierwill represent a difference between two statlons, and in that instance,with the average commercial variable condenser, the operator merelymakes the best guess he can and sets his pointer accordingly, some timesusing a rubber-tipped pencil to adjust the knob slightly to bring it tothe final position. The results are seldom highly satisfactory, and thepresent invention fully overcomes this difficulty by enabling a far moreaccurate and much finer adjustment than possible when a pointer andordinary vernier graduation are depended upon.

Referring to the drawings by numerals, 1 indicates any ordinary housingfor radio apparatus having the usual front or instrument anel 2. Thepresent improved condenser 1s mounted relative to said housing andpanel, and consists of fixed and movable leaves, and means for actuatingthe movable leaves. The condenser parts, including the leaves, may bearranged at any point found desirable within the housing 1, as, forexample, in a central portion thereof, while leaving the part adjacentthe panel and other side portions free for distribution of other radioreceiving apparatus,

such as tuning and ampli ing tubes, and other well known devices. t isone of the essential advantages of the present invention that thecondenser adapts itself to location enabling all of the radio parts tobe mounted v with greatest facility both with respect to theirco-relation and with the assurance of the shortest possible wiring.

Mounted within the housing 1 is theframe 3 for the variable condenser,which frame will be proportioned, of course, accordingto the size of thecondenser, a multiple tjndenser being illustrated, that is, a fondensermade up of a series of independent condensers adapted to be successivelyswitched into operative relation by switches 4,' 4, as higher and higherwave lengths are to be received. Each of the units of the condenser is aduplicate of the others. One only, therefore, will be specificallydescrib ed, and thesame reference numerals and dt lim lized as required.Also, it will be obvious that the number of plates illustrated may bevaried for each unit to any extent found desirable without the slightestdeparture fromI the scope and `intent of the invention.

The frame 1 is divided into as many compartments as there are condenserunits, and within each compartment are fixedly mounted a series ofspaced condenser plates 5, 5, which are electrically connected in theusual manner. Between each two of these plates iS arranged a movablecondenser plate 6. The several plates 6 are pivoted, at 7, and carefullyinsulated from the other plates, one set of the plates being connectedto one side of the circuit and the other set to the other side. A crossbar 8 connects the free ends of all of the plates 6, and is pivotallyenraged by an arm 9 (see Figure 4) depending from an actuator. The saidactuator preferably consists of a slide'10 mounted in and guided by atube or like guideway l1 curved to conform with the path of travel ofthe free ends of the plates 6 `when swung upon their pivotsJ-The tube 11is formed with a lateral slot 12, and the arm 9 is formed integral orappropriately fixed to the slide 10, extends laterally therefrom throughthe slot 12, and is then bent to a position for pivotally engaging thecross bar 8. Thus, shifting of the slide 10 will effect correspondingswinging movement of the several plates 6 engaged by the respective bar8. The sever-` al guideways or tubes llmay be formed of any appropriatenon-metallic substance, and may be otherwise shaped than as tubes, butin tubular form serve effectively to contain and direct the actuatingcable 13 which engages the slide 10 and extends longitudinallythroughout the guide or tube 11. The guide or tube 11 in each instanceextends' for a sufiicient distance for directing the cable 13,

and the cable extends thence to the panel control 14. for the condenser.As seen in Figures 1 and 3, tube 11, after completing its arc conformingto the stroke of the movable plates, loops to direct the cable 13 into aline at right angles to the planes of the movable plates 6, but the saidtubes may be otherwise shaped when the condenser is otherwise locatedrelative to the panel, as, for instance, as seen in Figure 9, and aswill be hereinafter mentioned.L Any position whatever of the controls14C is possible with this arrangement, different in location merelyrequiring the appropriate shaping of the tube or guideway 11. The cable13 is preferably a non-conducting cord, but may be of any appropriatematerial. In this structure also, gravity is' depended upon for thereturn of the plates 6 to position between plates 5, but provision/maybe made for positive return when desired after the manner indicated inFigure 9 as will be hereinafter described. f

It will be apparent that the several plates 6 will assume that relationto the plates 5 afforded by the location of the slide 10, which may beadjusted to a nicety b y the panel control 14, as seen in detail in Figures 5 to 8 inclusive. Each anel control for a condenser unit is aduplicate of the others, and but one istherefore, illustrated and willbe described in detail. The panel Control consists of an elongatedhousing adapted to be anchored to the face of the panel and having anelongated slot 15 through which extends the thumb piece 16 of a block 17carried by a slidev18 mounted and'adapted to slide within the housing, apart of the slide 18 extending into the slot 15 and being guidedtherein. The sides of the wall of the housing along the longitudinaledges of slot 15 are preferably graduated, and the thumb piece 16preferably terminates in pointers 19', 19, adapted to cooperate withsaid graduations. The said graduations take the place in this apparat-usof the vernier graduations of the ordinary commer- .cial variablecondenser. The slide 18 is hollowed out and formed with an elongatedslot-like recess 20 for accommodating the block 17 ,'so that the blockmay be shifted along and within the slide 18 independently of anymovement of the slide itself. To facilitate this independent shifting ofthe block 17, the block is mounted preferably on a screw-threadedspindle 21 arranged longitudinally of the slide-18, and having its endsjournaled in the ends of the slide 18. One of the end portions of thespindle 2l extends suiiciently beyond the end of the slide 18 to receiveand lixedly carry a knurled head or`other appropriate operating handle22, so that, when the head 22 is revolved, the spindle 21 is likewiserevolved, and the block 17 is caused to travel lengthwise of slide 18independently of any movement of said slide 18. The cable 13 extendsthrough a guiding tube 23 into the housing for slide 18, the tube 23being bent downward to direct the cable 13 toward said slide 18. Thecable extends through the upper end portion of the slide 18 and is fixedto the block 17, an aperture 24 bein formed in the upper end portion'ofthe sli e 18 for accommodating free longitudinal movement of the cable13 independently of the slide 18.

I he slide 18 preferably frictionally engagesv the surrounding housingvso as to remain in any given adjusted position. Thisl stressedbyfsprings 26, 26, so that said plungers constantly' frictionally engagethe in- I ner surface of the side walls of the housing for slide 18,and, accordingly, frictionally retain the slide at any point at whichVit happens to be left.

In operation, the thumb piece' 16 is grasped and the slide 18 is therebyshifted up and down for adjusting the plates of the 1 condenserf aslrequired for tuning in. lVhen the operator 1perceives that he i sapproximately in the eld desired, he discontinues movement of theslide18. He then and basa memoranda on the subject, the

l a slightly second time he desires to locate the same, his work isgreatly facilitated, but the opera-- tion will bepractically the same.The extended movement of the plates 6 is accomplished quickly, and thenthe finer adjustment obtained by the slower method of threading theblock 17 to the required position by operation of the disc 22.

The adaptability of the invention to every known form of receiving setshould be apparent and the great utility of freedom of location of thearts with assured nicety of adjustment is ound effective in everyinstance. This adaptability extends to the point of location of thecondenser otherwise `than in the usual horizontal position. For

instance, the moving plates may be arranged to swing horizontallyinstead of vertically in which case they would not drop back by gravity,and I have illustrated in Figure 9 modified embodiment of the invention1n which the structure is otherwise identical but which is especiallyadapted to enable use of the condenser regardless of its location or ofthe effect of gravity. In this construction, the usual fixed plates 5and pivoted plates 6 are employed. The plates 6 are connected by theusual cross bar 8 pivotally engaged by the arm 9 Acarried by the slide10 within the guideorl tube 11". 'Ihe guide or tube 11 invthis instance,howover, not only extends in an arc upward from the lowermostlocation-ofthe free end of the plates 6 but also extends downward and acable 13 engages the slide 10 at vone side, and a cable 13 engages theslide 10 at the other side. The two cables extend one into the upper endand the other into the lower end of the housing 14 at the panel, and thetwo cables meet at the block 17 which is carried in the slide 18!mounted in housing 14. The usual threaded spindle 21 engages the block17 and is provided with the operating knurled disc 22 for enabling therefined adjustment of the cables 13 and 13 after the main adjustmentthereof incident to shifting the slide 18.

Thus it will be seen that the structure seen in Figure 9 parallels inform and function that seenA in Figure 3 and described in detail above,except for a slightly different location of the, control housing and forthe affirmative return motion of the pivoted plates which enables oeration thereof regardless of gravity an regardless of positionin of thecondenser.

It s ould be observed that the knob attached t an axialshaft of a rotaryvariable condenser has relatively slight movement. The periphery of theknob travels only a very small fraction of the distance which theperiphery of the disc fragments travel. Therefore, the verniergraduations for the needle of the knob must be .extremely fine forindicating any substantial degree of fineness of adjustment of thecondenser. By contrast, the present invention has its indicator moverelative to the movement of the peripheral portion of the moving plate,or more accurately that portion of the moving'platemost remote from theaxis of the pivot. Therefore, the indicator of each control 14 possessesthe capacity for the maximum amount of movement for any given movementof the movable lates, and the graduations on the face of t e housing ofcontrol 14 are proportionately and relatively magnified while actuallyoffering ample space for refinement of adjustment of the ointer.

W at is claimed is:

1. In variable condensers, the combination of a stationary element andan element movable relative thereto, flexible means for moving themovable element, `and means sustained by the flexible means forindicating the extent of movement of the movabley element.` ,l

2. The combination with a housing and a variable condenser therein, of aflexible cable connected to the movable element of the condenser andextending to the exterior of the housing.

3. In al variable condenser, the combination, with a stationary element,of an elongated element pivoted substantially at one end to swingrela-tive to the stationary element, andflexible means engagingsubstanti ally the other end of the elongated element for swinging thesame.

4. In variable condensers, the combination with a stationary element andan element movable, relative thereto, of flexible means formovingthemovable element, and a guide for fthe flexible means directingthe sameat an/angletothe path of movement of the movable element.

lll() 5. In variable condensers, the combination with a stationaryelement and an element movable relative thereto, of flexible means lill"guide to and for moving the latter, and a tubular guide for theliexible means. j 6. In variable condensers, the combination with astationary element and a movable element, of a tubular guide disposedadjacent the movable element, exible actuating means for the movableelement arranged in the guide, and rigid means extending from the guideto and engaging the movable element. Y

7. In variable condensers, the combination with a stationary element anda movable element, of a tubular guide disposed adj acent the movableelement, flexible actuating means for the movable element arranged inthe guide, and rigid means extendin from the pivotally engaging t emovable element.

8. In variable condensers, the combination with a stationary element, amovable elem'ent, of flexible means for actuating the movable element, aguide for the flexible means, a slide carried by the guide and engagedand actuated by the flexible means, and means of connection between theguide and the movable element.

9. In variable condensers, the combination with a stationary element anda pivoted element, of a guide extending along the path of movement ofthe pivoted element, a slide carried by the guide, an arm carried by theslide pivotally engaging the pivoted element, and liexiblem'eansengaging the slide for actuating the same.

10. In variable condensers, the combination with a stationary elementand a pivoted element, of aguide arched to conform to the path ofmovement of portions of the pivoted element, a slide mounted on theguide, means of connection between the slide and pivoted element forimparting motion from the slideto the pivoted element, and means ing theslide along the guide.

11. In variable condensers, the combination with a stationary elementand a pivoted element, of a tubular guide arched to conform tothe pathof movement of parts of the movable element, a slide mounted in theguide; the guide having a lateral slot, an amr outstanding from theslide and pivotally enfor shiftvgaging the movable element, and meansfor shifting the slide along the guide.

12. In variable condensers, the combination with. stationary element anda movable element, of a slide spaced from the movable element, meansfiexibly connecting the slide to the movable element for shiftin themovable element when the slide is shlfted, and means for shifting theslidef 13. In variable condensers, the combination with a stationaryelement and a movable element, of a slide spaced from the movableelement, means connecting the slide to the movable element for shiftingthe movable element when the slide is shifted, and iiexible means forshifting the slide.

14. In variable condensers, the combina,

tion with a stationary element and a movable element, of an indicatorslide spaced therefrom, a slide adjacent and connected to the movableelement for shifting the same, and means for transmitting movement fromthe indicator slide to the second-mentioned slide.

15. In variable condensers, the combination with a stationary elementand a movable element, of -an indicator slide spacedl therefrom, a slideadjacent and connected to the movable element for shifting the same, and

slide disposed exteriorly of the panel, and

means for transmitting motion from the indicator slide to the movableelement.

18. In variable condensers, the combination with a stationary element, amovable element, a housing therefor, a panel spaced from the housing, ofan indicator slide disposed exteriorly of the panel, means fortransmitting motion from the indicator slide to the movable element, andmeans movable relative to the indicator slide for further shiftin themovable element.

19. n variable condensers, the combination with a stationary element anda movable element, of an indicator slide spaced therefrom, a blockmovably mounted on the slide, and a flexible connection between theblock and the movable element for im arting movement from the block orthesli e to the movable element.

20. In variable condensers, the combination with a stationary elementand a movable element, of an indicator slide spaced therefrom, a blockslidingly carried by the slide, and means for transmitting motion fromthe slide and from the blockto the movable element.

21. In variable condensers, the combination with a stationary elementand a movable element, of an indicator slide spaced therefrom, a blockslidingly carried by the slide, means for transmitting motion from theslide and from the block to the movable element, and threaded means foractuating the' block.

l22. In a variable condenser, the combinarespect to the stationaryelements, of an function relative to eacl other without the actuator,and a threaded actuator carried by the first mentioned actuator, andmeans connecting' both actuators to the movable elements, each. actuatorbeing adapted to function relative to the other without the necessityfor retro ade movement. i

23. In a varia le condenser, the combination, with a plurality ofstationary elements, a pluralit of elements movable relative thereto, oan actuator for actuating the movable elements, and means carried by theactuator for the efectin of finek adjustments of one of the movable eements, the actuator and iine adjustment means being adapted tonecessity for retrograde movement.

20 W 24. In a variable condenser, the combina'.

tion, with stationary elements and elements movable relative thereto, ofan actuator flexibly connected with the movable elements l actuator andline adjustment means being adapted to function relative to each otherwithout the necessity for retrograde'movement.

25. In variable condensing apparatus, the combination of5 means forindicating movements of the movable velement of a condenser, means formoving the indicatin means to a neral adjustment, and means or moving te indicatlng means to a refined 'adjustment, the refined adjustmentmeans having means adapted for indicating the relative calibration ofboth saidV adjustments.

26. In apparatus of the class described, the combination, with astationary element and an element movable relative thereto, of

flexible means for moving the movable element, and iding means for theflexible means for directing the same into a path of movement at anabrupt angle to the path of movement of the movable element. 27. Inapparatus of the class described, the combination, with a stationaryelement and an element movable relative thereto, of a exible cableengaging the movable element for moving the same relative to thestationary element, and uiding means for the cable for enabling shiftingthereof in a direction different at the place beyond the guiding meansfrom the .direction of shiftmg of the cable at the place approachmg theguiding means.

In testimony whereof I aix my signature.

JAMES LYONS, Jn.

